The invention relates to a shelf unit, and more particularly, to a shelf unit that can be stacked atop a lower shelf unit to form a shelf assembly.
Various types of stackable shelf units are well known in the art. Stackable shelf units having a top, bottom and two opposing sides are known in which legs extending downwardly from the two sides of the shelf unit overlap the outside of the top portions of the sides of a lower shelf unit when the shelf unit is placed atop the lower shelf unit so that the bottom of the shelf unit is flush with the top of the lower shelf unit. However, the legs of the shelf unit are not secured to the lower shelf unit in any way, and thus, a stack of such shelf units is not as stable as it might be and can not support the loads that it might if the stack of shelf units were more stable.
Similarly, U.S. Pat. No. 1,648,025 to Molloy discloses stackable baskets which have legs that overlap the top portion of a lower basket when the basket is placed atop a lower basket. U.S. Pat. Nos. 921,694 to Hall and 4,444,320 to Chap and British Pat. No. 943,443 to Carroll et al. describe a basket, shelf and rack, respectively, wherein the legs of the basket, shelf or rack simply rest on top of the lower basket, shelf or rack. U.S. Pat. Nos. 2,600,191 to Beach and 4,079,836 to Von Stein et al. and British Pat. No. 1,297,910 to Hago Products disclose rack, basket and rack assemblies, respectively, wherein the legs of the rack or basket are inserted between horizontal members on the sides of a lower rack or basket when the rack is placed atop the lower rack or basket. Various means of securing baskets and racks are known in the art in order to increase the stability of the stacks. Such units have been secured together by a pin as in U.S. Pat. No. 2,836,304 to Furrer or hooked together as in U.S. Pat. No. 4,456,125 to Chap.
Thus, it is desired to develop a stackable shelf unit that can be secured to a lower shelf unit in such a way that the stack is stable and can support heavy loads.